Railway truck snubbing indication arrangement

ABSTRACT

In a railway truck wherein friction shoes are operatively carried in wedge pockets of the bolster and are urged upwardly and outwardly by one or more springs between the bottom of the friction shoe and the truck side frame, an opening defined by said bolster through which a surface of said friction shoe is viewable thus indicating the extent of wear of said shoe and the amount of useful life remaining for said friction shoe.

United States Patent 1 91 Neumann et a1.

RAILWAY TRUCK SNUBBING INDICATION ARRANGEMENT Inventors: Otto WalterNeumann, Chicago;

Frank Joseph Korpics, Streamwood, both of I11.

Assignee: Amsted Industries, Chicago, 111.

Filed: July 18, 1972 Appl. No.: 272,760

US. Cl. 105/197 DB, 105/197 D, 267/9 A Int. Cl. B61f 5/06, B61f 5/12,F16f 13/00 Field of Search 105/197 D, 197 DB, 193;

References Cited UNITED STATES PATENTS 3/1961 Wulff et a1. 105/197 DB9/1967 Tack 105/197 DB Primary Examiner-Gerald M. Forlenza AssistantExaminer-Howard Beltran 5 7] ABSTRACT In a railway truck whereinfriction shoes are operatively carried in wedge pockets of the bolsterand are urged upwardly and outwardly by one or more springs between thebottom of the friction shoe and the truck side frame, an opening definedby said bolster through which a surface of said friction shoe isviewable thus indicating the extent of Wear of said shoe and the amountof useful life remaining for said friction shoe.

5 Claims, 7 Drawing Figures RAILWAY TRUCK SNUBBING INDICATIONARRANGEMENT This invention relates to railway car trucks and moreparticularly to a type of truck wherein snubbing means is mounted ineach end of the bolster for cooperation with friction plates or panelson the adjacent side frame columns.

The present invention contemplates the provision of a visual wear limitindicator in the end portion of the bolster adjacent each of thefriction shoes which are operatively disposed in wedge-shaped pockets atopposite sides of the bolster and near each end thereof.

In the prior art various trucks have been proposed and a number havebeen placed in service wherein bolster oscillations are damped byfriction devices usually some form of friction shoe associated with thebolster for developing friction to resist its oscillations. Sucharrangements have been generally successful in eliminating harmonicaction of the bolster-supporting springs and the resultant harmfuleffect well known to those skilled in the art. However, it is commonlyknown that satisfactory results are obtained using the variousarrangements only in the event that the friction parts, mainly thefriction shoes, are not allowed to develop a condition of excessivewear; because the existence of such a condition will in turn cause thesprings associated with the respective friction parts to exert a forcewhich is out of tolerance and thus becomes ineffective in dampeningbolster oscillations.

Therefore in an effort to insure that the undesired harmonic action ofthe bolster-support springs is eliminated, it has become necessary toestablish as a part of a regular maintenance program whereby the wear ofthe friction shoes can be monitored. Since the rate of friction shoewear is dependent on many factors such as the type of loads carried, thetype of terrain in which the car is used and even the climate in whichit is used, for this reason of servicing of the friction parts cannot bebased on any set standard such as time or distance traveled.

It has thus been determined that the only practical method by whichfriction shoe wear can be determined is by actually measuring the wearincurred by each individual friction shoe. To accomplish this result, itwas necessary that maintenance crews used a yoke-shaped gauge which wasusually inserted through an opening in the top of the bolster andengaged the friction shoe thereby measuring the extent of wear.

Considering that most railway cars have two trucks and each truckgenerally has four friction shoes of the type previously mentioned, onecan clearly see that such a maintenance program would be very timeconsuming and expensive.

Accordingly, a primary object of the present invention is to providemaintenance and service personnel with a wear status indicator whichwill reveal at a glance the exact condition of the snubbing parts.

A further object of the invention is to provide a novel wear statusindicator that will reveal the half worn condition for the snubbingelements and thereby informing maintenance and service personnel of theneed to insert a shim between the shoe spring seat and the top of thecontrol spring. This would restore control spring pressure toapproximately the level that existed under new conditions.

Another object of the invention resides in the fact that the wear statusindicator will clearly show the presence or absence of a shim thusmaking it easier to make a determination of whether a complete frictionshoe must be replaced in order to return control spring pressure withinspecified limits or whether the mere insertion of a shim will restorethedesired control spring pressures.

The foregoing and other objects and advantages of the invention willbecome apparent from the following specification and the accompanyingdrawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary sideelevational view of a railway car truck embodying the invention.

FIG. 2 is an enlarged view of the end portion of the truck bolster shownin FIG. 1 illustrating in detail the wear status indicator.

FIG. 3 is a fragmentary side view of the railway car truck side frametogether with a truck bolster constructed according to the presentinvention and assembled in their operative positions; portions of theside frame and the bolster being shown in section to better illustratethe improved constructions.

FIG. 4 is a fragmentary sectional view through a railway car truckillustrating a modified form of our invention, the view being in sectionand comparable to the sectional view of FIG. 1.

FIG. 5 is a perspective view of the friction shoe.

FIG. 6 is a fragmentary sectional view taken on line 6-6 of FIG. 4.

FIG. 7 is a fragmentary sectional view similar to FIG. 6 with theaddition of a shim between the lower surface of the friction shoe andthe top of the control spring.

Referring now to FIGS. 1 and 3, a portion of a railway truck may be seenwhich is of conventional construction and includes a pair of spaced sideframes. one of which' 10 is shown. Each side frame has a compressionmember 12 and a tension member 14 interconnected by spaced verticalcolumns 16 the sides of which form a window 18 (FIG. 3) substantiallyrectangular in shape with the upper portion 18a of the window beingslightly narrower than the lower portion 18b.

It should be understood that the railway truck for the purpose of thepresent disclosure may be considered identical at both sides thereof andfor the sake of brevity only that portion shown will be described indetail.

The window formed by the compression member 12, tension member 14 andspaced vertical columns 16 is adapted to receive the end of the bolster,generally indicated at 20. The lower suface 22 at the end of the bolster20 is supported by a plurality of support spring groups 24 which rest attheir lower ends on the side frame tension member 14. In opposite sidewalls 26 at each end of the bolster 20 are wedge-shaped receivingpockets 28 which open outwardly toward the side frame columns 16 andhave an inclined inner wall 30 which has a width correspondingsubstantially to the width of the wedge-shaped friction shoe 32positioned therein. The inclined inner wall 30 projects above the planeof the bolster top wall 34.

One wedge-shaped friction shoe 32 is operatively carried in each pocket28 and includes an inclined surface 36 corresponding to and frictionallyengaging the inclined wall 30 of the pocket 28 as well as a verticalsurface 38 for frictionally engaging vertical wear plates 40 on theadjacent side frame columns 16. The lower surface 42 of the wedge-shapedfriction shoe is engaged by the upper end of a control spring 44 whichis disposed between said friction shoe 32 and the tension member 14 ofthe side frame 10. The inclined inner wall 30 therefore provides aninclined thrust area equal to that of the engaged portion of theinclined surface 36 of the wedge-shaped friction shoe 32.

Located in the end of the bolster 20 and adjacent the outboard side ofeach respective friction shoe 32 is a wear status indicator showngenerally at 46.

The wear status indicator provides for the viewing of a portion of thewedge-shaped friction shoe and thus enables one to compare the presentposition of the friction shoe to a previously established reference. Theestablished reference point can either be a point that reflects the newunworn condition of the friction shoe or in the alternative, reflects apreviously established point which indicates a condition of maximumallowable wear for a friction shoe. Thus by comparing either of theestablished reference points to the present position of the frictionshoe one can readily make a determination as to the amount of wearremaining in the friction parts.

Additional reference points can be established on the wear statusindicator which correspond to conditions that will exist when otherserviceprocedures are to be performed. For example, a reference pointcould be established to indicate when a shim should be inserted betweenthe lower surface of the friction shoe 42 and the top of the controlspring 44 to insure that proper spring pressures are maintained.

It should be understood that the actual construction and arrangement ofthe wear status indicator could vary considerably depending upon thetype of railway truck and the type of car it is to be used with and theconditions which are to be indicated. FIG. 2 shows in detail a preferredembodiment of the wear status indication shown generally at 46 in FIGS.1 and 3.

The opening of the wear status indicator 46 is defined by the flatsurface of the web 47 located in the end of the bolster 20. The lowerportion 48 of the opening is substantially rectangular in shape withthree sides of the rectangle being defined by the surface of the web 47the left side 49 and right side 50 being substantially parallel to eachother and perpendicular to the lower side 51. The upper portion 52 ofthe opening is also substantially rectangular in shape but each of thedimensions of the upper rectangle being less than the respectivedimension of the lower portion 48 of the opening. Three sides of theupper portion 52 of the opening are also defined by the web 47 with theleft side 53 and right side 54 of the upper portion 52 beingsubstantially parallel to each other and parallel to the vertical sides49 and 50 of the lower portion 48 of the opening. The upper side 55 ofthe upper portion 52 forms the top of the wear status indicator 56which'is substantially parallel to the lower side 51 of the lowerportion 48 of the opening which also forms the bottom of the wear statusindicator 46. The fourth side of both the upper and lower rectangularportions 48 and 52 of the: opening are common to one another. However,due to the difference in dimensions of the two rectangles, shoulders 56are formed at the points of intersection of the two portions 48 and 52of the opening.

The wear status indicator 46 is to be constructed and positioned in theweb 47 of the end wall of the bolster 20 and extends through the wall tothe outboard wall 58 of the wedge-shaped bolster pocket 28 therebyproviding an unobstructed view of a reference index such as the frictionshoe spring seat 42. The lower portion of opening 48 of the wear statusindicator is so positioned that alignment of a reference index such asthe friction shoe spring seat 42 in said opening would exhibit theunwornor satisfactory condition of the snubbing parts associated withthat wear status indicator.

The same positioning of the wear status indicator 46 may also revealother conditions of the associated parts, For example, in the event thefriction shoe spring seat 42 is in alignment with the shoulders 56formed by the intersection of the upper and lower portions 52 and 48 ofthe opening respectively, the wear status indicator 46 would alertmaintenance and service personnel to the fact that the friction shoe 32should either be replaced or its effectiveness renewed by the insertionof a shim 60 between the lower portion of the friction shoe spring seat42 and the control spring 44 thereby restoring proper column pressure tothe control spring In the event the spring seat were aligned with theupper side of the upper portion 52 of the opening, this would establishthe maximum rise limit for the friction shoe 32 and would indicate atotally worn condition. If a shim had previously been inserted betweenthe lower portion 42 of the friction shoe 32 and the control spring 44,the maximum rise limit would be reached when the lower portion 42 of thefriction shoe 32 aligns itself with the upper side 54 of the top portion52 of the wear status indicator opening.

It should be understood that the term opening is meant to include theuse of any translucent material such as glass or plastic which mayeither be mounted in or cover the perforations in the end of the bolster20 which constitutes the upper and lower portions 52 and 48 respectivelythat are part of the wear status indicator opening.

- Referring now to FIGS. 4 through 7 there is shown another embodimentof the present invention wherein a protrusion or pointer arm 62 isattached at one end thereof to the friction shoe 32, the other end ofsaid pointer projects or extends through a slit defined by the web 47 inthe end of the bolster 20. The slit extends from the outboard wall 58 ofthe bolster pocket 28 through the end of the bolster 20. Thus, alignmentof the pointer arm with previously established indices (not shown) onthe end of the bolster will enable service and maintenance personnel toreadily determine the condition of the snubbing parts associated withthat pointer arm.

As previously mentioned, upon the establishment of a half worn conditionfor the friction parts, the column pressure of the control springs 44may be restored by the insertion of a shim 60 between the spring seat 42of the friction shoe 32 and the top of the control spring 44.

Assuming the pointer arm 62 shown in FIG. 6 indicates the half worncondition of the friction shoe, maintenance crews could insert a shim 60as shown in FIG. 7 thereby restoring the column pressure of the controlspring 44 to its original value.

The maintenance procedure described above would reduce the wide range ofspring pressures that would otherwise exist if the friction shoe 32 wereallowed to remain in service until totally worn out. By limiting therange through which the column pressures may vary by the utilization ofa shim 60, more effective snubbing action may be maintained throughoutthe life of the friction parts. This improved snubbing action isaccomplished without the high cost that would be associated with thecomplete renewal of the friction shoe 32 and its associated parts;especially when said friction shoe and parts are only in a half worncondition.

The terms and expressions which have been employed are used as terms ofdescription and not of limitation, and there is no intention, in the useof such terms and expressions, of excluding any equivalents of thefeatures shown and described or portions thereof, but recognize thatvarious modifications are possible within the scope of the inventionclaimed.

We claim:

1. In a railway car truck including a bolster resiliently supported onspring groups in side frames between spaced vertical columns thereof,said bolster defining pockets on both sides thereof, friction shoe meanswedgingly interposed between said pockets and said vertical columns,compressed spring means for urging said friction shoe means into wedgingfrictional engagement with said pockets and said vertical columns, the

improvement wherein the bolster defines an opening through which areference index segment on said friction shoe means is viewable andaligned with said opening only during the useful life of said frictionshoe means; said reference index moving vertically across said bolsterdefining opening in direct proportion to the wear of said friction shoemeans.

2. The invention according to claim 1 wherein said bolster openingcomprises distinguishable first and second portions, said referenceindex segment on said friction shoe means being viewable through andalignable with either of said portions throughout the useful life ofsaid friction shoe means.

3. In the invention according to claim 2, wherein viewable alignment ofsaid reference surface of said friction shoe means between said firstand second portions indicates wear and the requiring of service for saidfriction shoe means.

4. In the invention according to claim 1 wherein said bolster definedopening comprises a upwardly extending slot.

5. In the invention according to claim 4 wherein said friction shoemeans including pointer means extending through said slot.

PatentNo. 3,805,707 Dated April 23, 1974 Inventm-(s) Otto Walter Neumannand Frank Joseph Korpics It is certified that error appears in theabove-identified patent ,and that said Letters Patent are herebycorrected as shown below:

I In the Abstract: In Line 2, after "wedge" insert --shaped.

In the Claims: v In Column 6, Line 6, after "index" insert --segment--;

In Column 6, Line 7, delete "defining"; In Column 6, Line 16, delete"surface" and insert --index segment--; 7 1

In Column 6, Line 21, delete "defined"; In Column 6, Line 24, delete"including' and insert --index segment comprises-.

. Signed and sealed this 8th day of October 1974.

(SEAL) Attest:

f McCOY M. GIBSON JR. 0. MARSHALL DANN Attesting Officer Commissioner ofPatents FORM P041050 (10-69) USCOMM-DC 60376-P69 a us, GOVERNMENTPRINTING OFFICE: 1969 0-366-334

1. In a railway car truck including a bolster resiliently supported onspring groups in side frames between spaced vertical columns thereof,said bolster defining pockets on both sides thereof, friction shoe meanswedgingly interposed between said pockets and said vertical columns,compressed spring means for urging said friction shoe means into wedgingfrictional engagement with said pockets and said vertical columns, theimprovement wherein the bolster defines an opening through which areference index seGment on said friction shoe means is viewable andaligned with said opening only during the useful life of said frictionshoe means; said reference index moving vertically across said bolsterdefining opening in direct proportion to the wear of said friction shoemeans.
 2. The invention according to claim 1 wherein said bolsteropening comprises distinguishable first and second portions, saidreference index segment on said friction shoe means being viewablethrough and alignable with either of said portions throughout the usefullife of said friction shoe means.
 3. In the invention according to claim2, wherein viewable alignment of said reference surface of said frictionshoe means between said first and second portions indicates wear and therequiring of service for said friction shoe means.
 4. In the inventionaccording to claim 1 wherein said bolster defined opening comprises aupwardly extending slot.
 5. In the invention according to claim 4wherein said friction shoe means including pointer means extendingthrough said slot.